document.write( "Question 1097603: A factory owner buys a new machine for $21,000. After eight years, the machine has a salvage value of $3000. Find a formula for the value of the machine after t years, where 0 ≤ t ≤ 8. \n" ); document.write( "

Algebra.Com's Answer #712045 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
I assume it's a straight line relation
\n" ); document.write( "Plot $\"+v+\"$ on vertical axis
\n" ); document.write( "Plot $\"+t+\"$ on horizontal axis
\n" ); document.write( "------------------------------
\n" ); document.write( "The slope is $\"+%28+3000+-+21000+%29+%2F+%28+8+-+0+%29+\"$
\n" ); document.write( "slope = $\"+-18000%2F8+\"$
\n" ); document.write( "slope = $\"+-2250+\"$
\n" ); document.write( "-----------------------
\n" ); document.write( "Use the general point-slope formula
\n" ); document.write( " $\"+%28+v+-+3000+%29+%2F+%28+t+-+8+%29+=+-2250+\"$
\n" ); document.write( " $\"+v+-+3000+=+-2250%2A%28+t+-+8+%29+\"$
\n" ); document.write( " $\"+v+-+3000+=+-2250t+%2B+18000+\"$
\n" ); document.write( " $\"+v+=+-2250t+%2B+21000+\"$
\n" ); document.write( "---------------------------
\n" ); document.write( "check:
\n" ); document.write( "When $\"+t=0+\"$
\n" ); document.write( " $\"+v+=+21000+\"$
\n" ); document.write( "OK
\n" ); document.write( "When $\"+t=8+\"$
\n" ); document.write( " $\"+v+=+-2250%2A8+%2B+21000+\"$
\n" ); document.write( " $\"+v+=+-18000+%2B+21000+\"$
\n" ); document.write( " $\"+v+=+3000+\"$
\n" ); document.write( "OK \n" ); document.write( "

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